The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The designs for some vehicles limit the space available for a single section fuel tank with enough fuel capacity for the vehicle. For these vehicles, either multiple fuel tanks or multiple section fuel tanks such as saddle tanks have been developed. Typical fuel delivery systems draw fuel from a single inlet and with the incorporation of a multiple section fuel tank, either multiple fuel inlets have to be developed or systems for equalizing the fuel in the separate sections of the fuel tank need to be incorporated.
While systems have been developed for multiple inlets, the independent drawing of fuel from the multiple sections leads to the problem of unequal levels of fuels in the multiple sections due to unequal drawing of the fluid from each section. Systems have also been developed for transferring fuel between various sections of the fuel tank to equalize the fuel level in each section. In one system, in a saddle type fuel tank, fuel is siphoned between a fuel tank sub side and a fuel tank main side within which is located the fuel pump module, which pumps fuel to the engine of the vehicle. The siphoning action is started and maintained by having the fuel pump module pump a portion of the fuel to the fuel tank sub side to purge gas from the siphon line which then transfers fuel to the fuel tank main side when unequal levels of fuel exist.
In other systems, a jet pump of the fuel pump module operates to draw fuel from the fuel tank sub side to the fuel tank main side. In order to maintain an uninterrupted supply of fuel to the engine, the jet pump of the fuel pump module must be submerged in fuel at all times to maintain its primed state in order to transfer fuel from the fuel tank sub side to the fuel tank main side. If the jet pump of the fuel pump module is not maintained in a primed or submerged condition, the transfer of fuel from the tank sub side to the tank main side may not be maintained and thus, uninterrupted supply of fuel to the engine may not be maintained.
During instances of quick vehicle maneuvering, sloshing of fuel from the fuel tank main side to the fuel tank sub side may occur. When this occurs, an instant imbalance of fuel levels between the fuel tank main side and the fuel tank sub side occurs. While current transfer lines between two sections of a fuel tank are designed to eventually equalize the fuel levels, they do not have the fuel transfer volume capability to equalize this sloshed fuel imbalance quickly. This may result in an excess amount of fuel in the fuel tank sub side and an insufficient amount of fuel in the fuel tank main side leading to a loss of priming for the jet transfer pump. Ultimately, this may result in losing the uninterrupted supply of fuel to the engine, even though the fuel tank sub side has sufficient fuel to be transferred to the fuel tank main side.
In situations where fuel sloshing occurs in the opposite direction or from the fuel tank sub side to the fuel tank main side, current transfer systems will equalize the fuel levels by transferring fuel from the fuel tank main side to the fuel tank sub side. This is an unnecessary transfer since the fuel that has been transferred to the fuel tank sub side from the fuel tank main side will eventually have to be retransferred back to the fuel tank main side.